Biography is usually a safe profession. Even rather sedate. But more than one biographer has found that writing about the late great mathematician Gideon Summerfield leads to a hasty retreat. Or something more deadly...

Imogen Quy, the coolly competent college nurse at St. Agatha's College, Cambridge, first notices the pattern when her enthusiastic lodger Fran becomes the latest Summerfield biographer. Before she realises how deadly the Summerfield secret is, Fran's life is in danger. And Imogen may be next...